1. Field of the Invention
The present invention relates to an image forming apparatus which enables easy management of proofs in a printing process, a control method therefor, a control program and an image forming system.
2. Description of the Related Art
In a conventional printing process such as a process by an offset printing machine, a picture of a printed matter is reproduced in desired gradation by printing a plurality of sample outputs for proofing (proofs) for which adjustment parameters have been variously adjusted by a sample-for-proofing printing machine called a proofer, for one image data received from a requester, such as PostScript data (a PS file), and adjusting the ink coating thickness based on color information about a proof selected from among the proofs (see Japanese Laid-Open Patent Publication (Kokai) No. 2002-326343).
In general, a color mark called a profiling target, which is created with a specified density parameter, is printed on a proof, and a computer calculates the value read from the color mark by a calorimeter or the like and creates a device profile to be a color adjustment basis for a printing machine. The color information described above corresponds to this device profile.
The adjustment parameters related to image formation by a proofer at the time when the proof is outputted are required in the case where the proof is reprinted or in the case where fine adjustment of proof output is performed again and again. The adjustment parameters are printed on a margin part of the proof or described on a printed matter physically different from the proof. The above-described profiling target is commonly written on a proof itself. In some cases, a multitude of profiling targets are written on margins of a proof. In other cases, a proof for confirming the profiling target is printed separately from a proof for confirming the reproductivity of image data.
In the above proofer, a considerable number of combinations of proofs for which color balance, basic color density and the like have been finely adjusted based on image data received from a requester are outputted at a time. A proof to be adopted is determined by comparing and reviewing them. Currently, a so-called ink jet printer or an electrophotographic printer is used as a proofer. Such a printer makes it possible to easily perform fine adjustment of parameters such as density, color balance and a gradation correction table, and therefore, a device profile to be adopted for printing is determined by outputting a multitude of proofs for which these parameters have been finely adjusted variously and comparing output results.
However, in the method in which printing is managed by printing adjustment parameters of a proofer on a sheet different from a proof, an input mistake of an adjustment parameter by a person easily occurs, and it is not easy to certainly associate a multitude of outputted proofs and a multitude of adjustment parameters with one another.
In the method in which adjustment parameters of a proofer are written on a margin, it cannot be strictly said that a proof and a final output matter are the same data if a setting information image, such as characters, put on the margin is considered, and there is therefore a problem that it is difficult to grasp the image of a final output matter.
Furthermore, when the adjustment parameters of a proofer are reset, it is necessary to input a multitude of adjustment parameters. Therefore, it is conceivable that an input mistake by a person similar to the above frequently occurs.
Furthermore, the method in which a profiling target for creation of a device profile is created on a margin of a proof has a problem that it is difficult to grasp the image of a final output matter because the appearance of the proof is not the same as the final printed matter.
In the method in which a proof for confirming a profiling target is printed separately from a proof for confirming the reproductivity of image data, the association relation between the proof for confirming the reproductivity of image data and the proof for confirming a profiling target tends to unclear, and there is therefore a problem that no means for ensuring that a profiling target corresponding to a desired proof has been certainly converted to a device profile for a printing machine exists.
Since there are a multitude of adjustment parameters of a proofer, and it requires skilled work and much work time to output a multitude of proofs by efficiently changing the settings. Further, since the adjustment parameters of a proofer or the device profile for printing machine described above include a multitude of parameters, the amount of data of a setting table or the like increases to collectively manage the parameters. Hereinafter, as more fine printing quality is required, it is required to efficiently manage the increasing data.